1. Field of the Invention
This invention relates in general to dryers and in particular to dryers of the type for drying grain or other materials.
2. Description of the Prior Art
Grain dryers are operated in remote areas where there are major fluctuations in the line voltage which cause inaccuracies in the operation of the drying machines. Also, due to the large size blowers and vibration associated with such machines, many electrical transients and noise problems exist which tend to cause inaccurate control and operation of the machines. It has been proposed to use thermistors or other heat sensors to detect temperature in a plenum chamber of a burner as well as within the material to be dried. However, since the air within the plenum chamber is very turbulent due to the violent movement of the air through the blowers into the plenum chamber and through the dryer the temperature sensed at discrete points may not truly indicate the average temperature within the plenum chamber or within the material being dried. Also, the direction of the wind can substantially change the temperature and amount of heated air passing through the material being dried at certain points as, for example, if the wind is from the north it will tend to resist air passing out of the dryer on the north side and will increase the passage of air through the south side of the dryer, thus, causing non-uniform air passage through the material and, thus, erroneous temperature indications can be obtained using discrete temperature point sensors.